Lubricating oil composition



Patented Feb. 14, 1939 Robert H. Gardner, Whiting, Sinclair Refining Company,

a corporation of Maine N o Drawing.

, Serial No.

Ind., assignor to New York, N. Y.,

Applicationflcptembcr 10, 1936,

'1 Claims. (01. 87-9;

My invention relates to improvements in compounded petroleum, lubricating oils. More particularly, my invention relates to improvements in the compounded lubricating oils described and claimed in an application of Arnold G. Vobach filed July 6,1936, Serial No. 89,120, now issued as Patent No. 2,081,075 of May 18, 1937.

The use of copper-lead and cadmium-silver and similar. special bearing metals in place of the formerly conventional babbitt metal in internal combustion engines has been increasing rapidly for some time. Such special bearing metals make possible the use of smaller bearing areas'per unit of bearing load, and thus make possible important reductions in the size and weight of engine parts and of the engine as a whole. Such weight reductions in turn make possible increases in the useful operating speeds of the engine and, as a consequence, increases in the power output per unit of weight. These special bearing metals have, however, lacked-the resistance to corrosion enjoyed by babbitt metal. At low and moderate temperatures copper-lead and cadmium-silver bearing metals, for example, have not exhibited any unusual tendency to deteriorate through corrosion, but as the temperatui'e of the lubricant increases, such alloys have exhibited an increasing tendency to deteriorate through corrosion, this tendency increasing rapidly with the temperature, using many it not most of the usual petroleum lubricating oils. Many addition agents have been proposed and some have been used to limit this tendency of petroleum lubricating oils to corrode such special bearing metals; 1 The compounded petroleum lubricating oils of said patent of Arnold C. Vobach sometimes exhibit this tendency to corrode such special hearing metals at'hightemperature. I have tried a number of the anti-corrosive addition agents proposed and used to limit this tendency of other lubricating oils, but the results I have obtained have not been consistent with the results obtained, or said to be obtained, with other lubricating oils.

I have, however, found that the addition of a. small proportion of elemental sulphur to petroleum lubricating oils comprising calcium phenyl stearate or a mixture of calcium stearate and calcium phenyl stearate, or the phenyl stearate or a mixture of the stearate and the phenyl stearate together with phenyl stearic acid, efiectively inhibits this corrosive tendency when it appears. The proportion in which I use the elemental sulphur ranges from 0.1% or somewhat less to 1.5%

stantially increased tion of Arnold C. Vobach,- plus of elemental sulphur.

or somewhat more, by weight on the compounded oil. I have found that the eiiect of the sulphur, as an anti-corrosive agent in these compounded lubricating oils, usually increases rapidly as the proportion in which it is used increases up to 5 about 0.25%, that its efiect usually continues to increase, but less rapidly, up to about 1% or 1.25%, and that its efiect is not usually subby its use in proportion much exceeding about 1.5%. The improved compound- 10 ed lubricating oils of my invention thus consist essentially of a petroleum lubricating oil and calcium phenyl stearate, or a mixture of calcium stearate and calcium phenyl stearate, or calcium phenyl stearate or a mixture of the stearate and 15 the phenyl stearate together with phenyl stearic acid, as described and claimed in said applicaa small proportion I claim: U 1. A liquid lubricating oil composition comprising a petroleum lubricating oil, calcium phenyl stearate and a proportion of elemental sulphur less than 1.5% by weight on the oil but suflicient to be effective to inhibit the corrosive tendency of the lubricating composition.

2. A liquid lubricating. oil composition comprising a petroleum lubricating oil, calcium phenyl stearate, calcium stearate and a proportion of elemental sulphur less than 1.5% by weight on the oil but suflicient to be effective to inhibit the corrosive tendency of the lubricating composition.

'3. A liquid lubricating oil composition comprising a petroleum lubricating oil, calcium phenyl stearate, phenyl stearic acid and a proportion of elemental sulphur less than 1.5% by weight on the oil but suflicient to be effective to inhibit the corrosive tendency of the lubricating composition.

-4. A liquid lubricating oil composition com-' prising a petroleum lubricating oil, calcium phenyl stearate, calcium stearate, phenyl stearic acid and a proportion of elemental sulphur less than 1.5% by weight on the oil but suflicient to be efiective to inhibit the corrosive tendency of the lubricating composition.

5. A liquid lubricating oil composition comprising a petroleum lubricating oil, a calcium soap of an organic acid containing an aromatic group, said soap having a decomposition temperature approximating the end point of said 011,

and a proportion of elemental sulphur less than 1.5% by weight on the oil but suilicient to be effective to inhibit the corrosive tendency oi. the lubricating composition.

6. A liquid lubricating oil composition comprising a petroleum lubricating oil, a calcium soap of an aromatic stearic acid and a proportion of elemental sulphur less than 1.5% by weight on the oil but sufllcient to be eflective to inhibit the corrosive tendency of the lubricating composition.

'7. A liquid lubricating 'oil composition comprising a petroleum lubricating oil, a calcium soap of an aromatic stearic acid, and a proportion of elemental sulphur less than 1.5% and more than about 0.1% by weight on the oil and sufficient to be efiective to reduce the corrosive tendency of the lubricating composition.

ROBERT H. GARDNER. 

